IHp = inner Helmholtz plane

FIGURE 1-11 Schematic representation of the electrical double layer. IHP = inner Helmholtz plane OHP = outer Helmoltz plane. 

Pig. 5-27. Contact ion adsorption on metal electrodes in aqueous solution IHP = inner Helmholtz plane OHP = outer Helmholtz plane i,d = adsorbed ion ih = hy-dratedion oM = charge on the metal electrode o i = charge of adsorbed ions o i = charge of excess hydrated ions in solution. [From Bockris-Devanathan-MuUer, 1963.]... 

Fig. 6-99. An interfacial electric double layer on semiconductor electrodes a = charge of surface states 0.1 = interfadal charge of adsorbed ions IHP = inner Helmholtz plane.

Fig. 7-2. Electron transfer of hydrated redox particles and of dehydrated adsorbed redox particles across an electrode interface (a) electron transfer of hydrated redox particles, (b) electron transfer of dehydrated and adsorbed redox particles on electrodes. (RED., OX,q) = hydrated redox particles (RED.d, OX.d) = dehydrated and adsorbed redox particles on electrode OHP = outer Helmholtz plane, IHP = inner Helmholtz plane.

Figure 4.11. Triple-layer model (Grahame) IHP, inner Helmholtz plane OHP, outer Helmholtz plane (, water dipole +, positive end of the dipole).

What, therefore, is the potential difference to be used Is it MzfraP< ), the potential difference from the metal to the contact adsorption plane, or IHP (inner Helmholtz plane, see Fig. 6.88), or is it MzfOHP<[>, the potential difference from the metal to the OHP (outer Helmholtz plane, see Fig. 6.88), or MzfSpotential difference from the bulk of the metal to the bulk of the electrolytic solution In respect to P, does one consider it to multiply the whole potential difference across the interface or only a fraction of this potential difference Similarly, what concentrations of electron acceptors and donors must be fed into the basic equation Bulk values or the values at the OHP or the values at the contact-adsorbed species (Fig. 6.88) ... 

Thus, Grahame modified Stem s model by introducing the inner plane of closest approach (IHP inner Helmholtz plane), which is located at the distance jc, from the electrode (Fig. 4.11). The IHP is the plane of centers of partially or fully dehy-... 

IHP Inner Helmholtz plane, see Helmholtz Double Layer. 

Figure 5.2 Model for the double layer region at the metai-eiectroiyte interface iHP, inner Helmholtz plane OHP, and outer Helmholtz plane (after [4]).

Fig. 2.1 Grahame s model of the electrochemical double layer. Anions and cations characterised by — or + signs, respectively. IHP inner Helmholtz plane and OHP outer Helmholtz plane. Reproduced from [19], with permission...

Figure 3. Schematic representation of an electrochemical double layer considered in Refs. 25, 26 S = solution Me = electrode IHP = inner Helmholtz plane OHP = outer Helmholtz plane Fh = potential drop in the Helmholtz layer Ko.ch = potential drop in the diffuse layer and x-distance from an electrode into solution.

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